Forty-six years ago, Harlem elected a Korean War veteran named Charles Rangel to the House of Representatives. For the first time since then, Rangel’s name will not be on the ballot on Tuesday.

In a crossroads election to replace the Lion of Harlem, voters in the 13th Congressional District will have the chance to chart a new course for an evolving section of New York.

What has become one of the most diverse congressional districts in America is now broader than 125th Street. A 2012 redistricting added a northwestern portion of the Bronx. Along with shifting demographics, what was once a solidly African-American district has become majority Hispanic. New arrivals have come from Africa, Central America, Bangladesh and elsewhere.

And the district itself has changed. When Rangel took office, drugs and boarded-up houses were scourges. Today, brownstones sell for upwards of $5 million. Many residents struggle to afford a room in an apartment. And yet city Housing Authority elevators break down. These are the challenges of gentrification.

Nine Democratic candidates hope to address the district’s issues, and in this Democratic stronghold, the winner of Tuesday’s primary is the overwhelming bet to go to D.C. The group includes many qualified contenders.

Keith Wright, a longtime state assemblyman and a lifelong resident of Harlem, represents the proud tradition of the neighborhood. Endorsed by Rangel, Wright understands the district’s history and its challenges. He leads the Manhattan Democratic Party and is the powerful chair of the Assembly housing committee. He has the support of the political establishment and would comfortably slide into Rangel’s old role.

Clyde Williams is a relative newcomer from Washington who worked for Presidents Bill Clinton and Barack Obama. Williams grew up in adversity, and some of his ideas represent the forward thinking the district needs — searching for alternate federal and private funding in an era of Republican-imposed austerity.

But the candidate with the best understanding of the modern 13th District is State Sen. Adriano Espaillat. A politician who has been an advocate for tenants and farmworkers, he displays a convincing understanding of the issues facing the entire district. His idea of a mitigation zone in Harlem to control the effects of gentrification is intriguing, and his nuanced understanding of the consequences of a broken national immigration policy is profound.

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Espaillat arrived without documents from the Dominican Republic, and would be a symbol for the many New Yorkers like him. In a new Congress in which immigration reform should be a defining issue, Espaillat would be a powerful voice for a federal Dream Act, a path to citizenship, and a curbing of the kind of deportation that splits families.

In prior runs for this seat, Espaillat relied on the kind of tribal bonds that have often powered NYC politics, and he will have to mend fences to transcend those barriers. He has said he wears his Dominican heritage on his sleeve, and his election would honor Dominican Americans and all immigrants. But he also displays the sensitivity to address the varied concerns of residents from Bedford Park to Manhattanville, an opportunity he should embrace. In this melting-pot district, a vision of the potential future of NYC, that will be uniquely necessary.